Comments on: CIDR Cheat Sheet http://www.countryipblocks.net/networking/cidr-cheat-sheet/ Security Solutions With Searchable IP Block Database Thu, 01 Dec 2011 02:24:39 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: Stewart White http://www.countryipblocks.net/networking/cidr-cheat-sheet/comment-page-1/#comment-1451 Stewart White Thu, 11 Nov 2010 17:45:04 +0000 http://www.countryipblocks.net/?p=389#comment-1451 each CIDR range you describe provides for a specific number of IP addresses For example: /16 = 65536; /24 = 256; /32 = 1 address/ xx.o.o.o/16 = xx.0.0.0 - xx.0.255.255 (65536 IP addresses) xx.0.0.0/24 = xx.0.0.0 - xx.0.0.255 (256 IP addresses) xx.0.0.0/32 = xx.0.0.0 (1 IP address) Based on the above you could add deny statements as follows: deny from xx.o.o.o/16 deny from xx.o.o.o/24 deny from xx.o.o.o/32 (or just "deny from xx.o.o.o") each CIDR range you describe provides for a specific number of IP addresses
For example: /16 = 65536; /24 = 256; /32 = 1 address/

xx.o.o.o/16 = xx.0.0.0 – xx.0.255.255 (65536 IP addresses)

xx.0.0.0/24 = xx.0.0.0 – xx.0.0.255 (256 IP addresses)

xx.0.0.0/32 = xx.0.0.0 (1 IP address)

Based on the above you could add deny statements as follows:

deny from xx.o.o.o/16
deny from xx.o.o.o/24
deny from xx.o.o.o/32 (or just “deny from xx.o.o.o”)

]]> By: Costas http://www.countryipblocks.net/networking/cidr-cheat-sheet/comment-page-1/#comment-1443 Costas Wed, 10 Nov 2010 19:09:34 +0000 http://www.countryipblocks.net/?p=389#comment-1443 Congratulations for the amazing work you are presenting us here. I am afraid I am relatively green in fully understanding the IP notation and I have a question: Suppose I wish to place a deny statement in my .htaccess file which includes a line for xx.0.0.0/16 or xx.0.0.0/24 or xx.0.0.0/32 what will be the range of IPs that will be denied in each one of the three cases. I am guessing that in the last one will be: xx.0.0.0 to 255.255.255.255 but I have the hunch that I am wrong. Thank you Costas - Toronto Congratulations for the amazing work you are presenting us here. I am afraid I am relatively green in fully understanding the IP notation and I have a question:
Suppose I wish to place a deny statement in my .htaccess file which includes a line for xx.0.0.0/16 or xx.0.0.0/24 or xx.0.0.0/32 what will be the range of IPs that will be denied in each one of the three cases. I am guessing that in the last one will be: xx.0.0.0 to 255.255.255.255 but I have the hunch that I am wrong.

Thank you

Costas – Toronto

]]> By: Dean Elliott http://www.countryipblocks.net/networking/cidr-cheat-sheet/comment-page-1/#comment-1113 Dean Elliott Thu, 29 Jul 2010 16:08:51 +0000 http://www.countryipblocks.net/?p=389#comment-1113 Nice work Stewart. Nice work Stewart.

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